Manufacture of photoflash lamps



INVENTOR A/EMVl/YA/DEM/YKW/M.

Filqd Jan. 26, 1940 M. J. N. DE MARGITTA MANUFACTURE OF PHOTOFLASH LAMPSATTORNEY Feb. 24, 1942.

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Patented Feb. 24, 1942 UNITED STATES PATENT OFFICE MANUFACTURE orrrio'roFLAsn LAMPS Michael J. Neumann dc Margitta, New York,

N. Y., asslgnor to Westinghouse Electric & Manufacturing Company, EastPittsburgh, Pa., a corporation of Pennsylvania Application January 26,1940, Serial No. 315,74 In Hungary September 5, 1939 8 Claims.

This application is a. continuation-in-part of my copending applicationon improvements in Flashlamps, Serial No. 298,276, filed October 6,1939.

The invention relates to lamps, and especially to photoflash lamps. isto provide a machine assembly for a cheap and i ya I Y Other objects andadvantages of the invention .will be apparent from the followingdescription and drawing in which;

Figure 1 is a front elevation with parts broken away of a preferred formof photoflash lamp.

Figure 2 is a cross-sectional view through a preferred type of apparatusfor assembling the photoflash lamp of Figure 1'.

Figures 3, 4 and 5 are views .in cross-section illustrating the varioussteps in the manufacture of the photoflash lamp with the apparatusillustrated in Figure 2. c

Figure 6 is an enlarged detailed view of the ,rim sealing step in theassembly of the photofiash lamp. 1

In Figure 1 is illustrated a preferred type of photofiash lamp describedin my above-referred to application. This photofiash lamp comprises aclosed end tubular casing or envelope to of plastic material, preferablycellulose acetate, al-

though various other compounds of the plastic group formed from resins,casein, pyroxylyn, shellac, etc. may be used.

The tubular casing or envelope ill has a. flange II at the open endwhich is sealed by a disk i2,

also preferably of a plastic material such as cel lulose acetate, andtwo conductors l3 and M are This application, in particular, describes aAn object of the invention quick manufacture of photoflash lamps inquan' member 22, having a central shaft 23. extending through the bottomof the base member H, for the purpose of expelling when desired, thecontents within the sleeve 2ll. The top portion 2|, of this member 22,is contoured to receive the top or envelope of the photoflash lamp,which is inserted with its top downward within the sleeve The positionof the member. 22 within this base member, is so that the flange II willrest upon the upper edge 25 of the sleeve 20.

The'tubular casing or envelope i0 has been filled with the combustiblematerial It, either prior to or after the tube has been inserted in thelower form H. The upper member comprises tubular member 26 having acentral opening 21 of a diameter to fit snugly around the projection IQof the lower base member. The lower member H has a compressible material28, such as rubber, around the base of the projection i9 whereby thetubular member 26 may be forced into a substantially air-tight seal withthe lower member H, as is illustrated in Figs. 3 and 5.

Within the central borek2l of the upper member, is a central projection29 having two holes 30 therein, in which the exterior connections of theconductors l3 and it maybe inserted and held therein, under somesecuringmeans, such as the spring 3|.

It will 'be noted that the base member i2 is thus held directly abovethe tubular portion ID, with the igniting means I5- pointing towards theinterior of the tube held in the lower portion I1.

preferred apparatus for quickly .and cheaply manufacturing such aflashlamp in quantity production. The machine comprises a-lower baseportion. ll whose upright projecting portion is has a central opening i8therein, extending downwardly. Within the central opening I8 is amovable'sleeve 20 having an inner diameter approximately the outerdiameter of the tubular casing or envelope ill of 'the flashlampj Thismovable sleeve 20 is preferably supported on a spring 2 I, from thebottom portion of the base ll.

In the bottom of the opening It is a. movable The sleeve 26 is loweredabout the tubular projection l9, and the rubber material 28 is com--pressed into .the substantially air-tight arrangement, as disclosed inFigure 3.

It will be noted that the surrounding sleeve 26,

has a port 32, located just above the flange of the inverted tubularcasing I0 when this sleeve is lowered into theposition of Fig. 3. Thebottom disc I2 with its igniting assembly; is' lowered, as illustratedin Figure 3, until it is in the neighborhood of this port. The centralspace 21 is substantially air-tight. The port 32 is connected to anexhausting machine for the removal of the air from the inner tube ll.Various ducts 33 are located in the lower case member .ll, so that therewill be no air pockets about the'tubular casing in to cause adulterationof the active gas.

After the air has been exhausted, anactive ga's isinserted through theport 32 to fill the inte j rior tube Hi to the desired pressure. Asprevi-' ously stated, this atmosphere may be oxygen and preferablyoxygen at a, pressure greater-than atmospheric.

The igniting device 15 on its base [I2 is then lowered .into the tubularcasing Ill, so that the periphery oi the base l2,presses against theupper surface of the flange H. A movable sleeve 34 is then lowered topress the base 02 against heat through the inner portions of the memberv29. This heating means is in contact with the movable sleeve 34, whichis of a material, such as copper, that will readily conduct the heatfrom the heating means to the plastic material. This material may alsobe of that used for high speed steels, chromium-silver-copper alloys,etc., that withstand the heat applied without oxidizing. The other partsmay be of brass, steel or other suitable metals or alloys. The electricheater could be embedded in this material instead of in the centralshaft.

An enlarged portion of the bottom edge of the fiashlamp, is disclosed inFigure 6. The hot cylinder 34 is pressing downward on the upper disc I2in contact with the flange ll of the tubular casing [0. Under both theheat and pressure, the plastic material softens and then forms ahomogeneous mass sealing the active gaseous atmosphere within theplastic casing ID.

The compression means, which may be manual, pneumatic-or hydrostatic,upon the bottom disc I! and the flange H, is removed and then the upper.portion of the assembling machine raised and the sealed and completedlamp is removed from the apparatus. While the sealing means has beenshown as a single unit, it may be one unit in a multi-head machine. 1

It is apparent, many modifications may be made in the particular formand method of assembling this device, and accordingly I desire only suchlimitations to be imposed upon the preferred method and apparatusdescribed herein, as are necessitated by the spirit and scope of thefollowing claims.

I claim:

1. The method of assembling the flanged envelope and base of afiashlamp, which comprises juxtaposing an annular laterally projectingarea of the flange upon a support thereby supporting the flanged end of.the envelope directly by its flange, juxtaposing the rim of the baseadjacent to the laterally projecting area of the flange,

enclosing both the envelope and base, exhausting the atmosphere in saidenvelope and replacing it with an active gas, bringing the rim of thebase into facial contact with the laterally projecting area of theflange, applying heat, and applying opposing pressure directly on theprojecting area of the flange and on the rim of the base next theperipheries thereof for squeezing those parts together and therebysealing the for filling said third member,-including said envelope withan active gas, and means for applying said base to said flange with heatand pressure to seal said envelope and base together.

3. Apparatus of the class described comprising a cylinder having ahollow center to hold one part to be sealed, a holding member for theother part having heating means therein adja- I for exhausting andfilling purposes.

4. Apparatus for assembling the envelope of a lamp to a lamp basecomprising a base member supporting said envelope, a movable memberholding said lamp base above said envelope, a

movable sleeve pressing said lamp base on said envelope and heatingmeans within said movable sleeve whereby saidenvelope and lamp base aresealed together.

5. Apparatus for assmbling the envelope of a lamp to a lamp basecomprising, a base member supporting said envelope, a movable memberholding said lamp base above 'said envelope, a movable sleeve pressingsaid lamp base on said envelope, heating means within said movablesleeve whereby said envelope and lamp base are sealed together, and asubstantially air-tight casing enclosing the preceding envelope, lampbase, member, sleeve and heating means, said casing having a port forexhausting and filling purposes.

6. Apparatus for assembling the envelope of a lamp to a lamp basecomprising a base member having a sleeve member supporting an edge ofsaid envelope, an upper assembly, said upper assembly having anenclosing member surrounding the portion of said base member having saidsleeve member, a movable sleeve member in said upper assembly having itsedge adjoining the edge of said sleeve member in the base member and asupporting member in said upper assembly lowering the lamp base on theedge of the envelope for sealing said envelope and lamp base together.

7. Apparatus for assembling the envelope of a lamp to a lamp basecomprising a base member having a sleeve member supporting an edge ofsaid envelope, an upper assembly, said upper assembly having anenclosing member surrounding the portion of said base member having saidsleeve member, a movable sleeve member in said upper assembly having itsedge adjoining the edgeof said sleeve member in the base member, asupporting member in said upper assembly lowering the lamp base on theedge of the envelope, and means for supplying heat to one of said sleevemembers whereby said envelope and base are sealed together.

8. Apparatus for assembling the envelope of a lamp to a lamp basecomprising a base member having a sleeve member supporting an edge ofsaid envelope, an upper assembly, said upper assembly having anenclosing member surrounding the portion of said base member having saidsleeve member, a movable sleeve member in said upper assembly having itsedge adjoining the edge of said sleeve member in the base member and asupporting member in said upper assembly lowering the lamp base on theedge of the envelope, and means for supplyingheat and pressure to one ofsaid sleeve members whereby said envelope and base are sealed together.

MICHAEL J. NEUMANN Dr: MARGITTA.

